I'd imagine it is difficult for the
causual or none technical fan to understand why there is such a
disparity in performance between the front runners and lower tier
teams. If we were to take Red Bull Racing and Caterham as examples
for this article we will see differentiators in performance. I have
decided to use these teams as an example as the 2010/11
Champions Red Bull are a team at the top end of their game.
Meanwhile Caterham joined the sport in 2010 (under the guise of Lotus
Racing and ran 2011 as Team Lotus before finally settling on the
Caterham marque). Caterham initially entered the sport using the
Cosworth engine and although they weren't quite upto the speed of the
established teams they did make their mark as the best of the 3 new
teams.
The main reason I have decided to use these two teams as the
reference points is due to their common use of the Renault engine but
also because Caterham purchase their gearbox and parts of the rear
suspension from the Red Bull Racing team (albeit the
Caterham uses the previous seasons setup, so for this year the RB7's
setup)

So why is there a performance
difference between the two I hear you ask. Well that may not be as
an easy answer as you would think. Firstly using last years
suspension setup means that you are using a geometry/layout that was
designed to cater for EBD (Exhaust Blown Diffusers) without the use
of this, this year the teams lack rear end downforce. Red Bull
utlised the quantity of air flow that could be generated through EBD
to run much more rake. Something that the teams this year would need
to start with much less of and as the season progresses and
additional airflow is scavenged through upgrades they can increase
the rake.

Rake for those that are unfamiliar is
the pitch angle of the car over its longitudinal distance (ie higher
at the rear than at the front, pointing downward) The reason for more
rake is as you find a way to add downforce on top the car you need to
balance this with creating more airflow under the car. Adding Rake
or raising the rear end can give the diffuser a larger cavity to flow
more air.

This obviously gives the Caterham
designers something to work around and results in a compromise that
will ultimately narrow the window in which the suspension can be
adjusted. With EBD now banned next year should see Caterham take
advantage of the RB8's design philosophy of which the RB9 will simply
be an evolution.

Infrastructure

Aerodynamically the
Red Bull team over recent years has had the jump on most of the
field, lead by Adrian Newey the Red Bull aero team are at the
forefront of F1 design. Red Bull embraced the transition from on
track testing to a less restrictive ability to design their cars in
the Wind Tunnel and CFD. They have also adopted the use of 3D
printing in order to rapid prototype parts and test them in the Wind
Tunnel environment, this speeds up a process that in the past may
have taken much longer to produce parts for testing. Red Bull have
many test rigs in order to analyse stress and performance of the car
either in it's entirety or individually. By designing the car at
this level it allows for a higher level of freedom in terms of
design, allowing you to test many components in a short amount of
time. As Caterham are a much younger team their level of
infrastructure is much less than Red Bull and so it will take time in
order for them to purchase and use the equipment and get the skilled
staff required to operate them. Red Bull also had a head start by
purchasing the pre existing Jaguar team and simply building on that
pre existing setup. Caterham however have started from nothing and
are working hard to replicate the infrastructure of teams like Red Bull.

The video below is a great
watch as it goes around the Red Bull factory circa 08/09 to look at
the ways in which the team approach the design of their F1 car. As
an emerging team i'm sure they continue to push the envelope and add
additional features to those shown but it gives a great idea of the
processes involved:

Engine / KERS Performance

Red Bull Racing began using the Renault
engine back in 2006 and has such has a fantastic understanding of how
to extract the best from the powerplant. Adrian Newey's designs
always centre around shrink wrapping the car and
making the bodywork as tight as possible. This is part of a match
made in heaven as the Renault engine is incredibly efficient and
requires less cooling than it's counterparts. Number's touted around
the paddock suggest that the Renault engine is down on overall power
in comparison compared to the Mercedes & Ferrari engines by
around 15bhp. This however is not a problem as the drive ability and
much better fuel consumption the engine produces can outweigh this.
It is said that the Renault uses around 15 Litres less of fuel over a
race distance, this equates to around 10KG's which in a race car is
essential weight that can be placed elsewhere.

Red Bull Racing's ongoing
technical partnership with Renault has also allowed them to perhaps
better understand the mapping requirements of the engine in
comparison to Caterham who are only in their second year of supply from Renault.

KERS is
something that both teams purchase from Renault Sport and can also
affect the balance of the car whilst in both the harvesting and
dispensing stages. Red Bull have more experience using the KERS system
and although they struggled initially with system failures they now seem
to be on top of the system. This being the first year that Caterham
have used the system they not only had to find a way to package the
system but also find a balance in order to gain additional lap time.
KERS also has an aerodynamic effect as additional cooling is required in
order to keep the batteries cool. (Imagine using a piece of electrical
equipment for a while and then fetching the battery out, you will
notice how warm it is. As electricity is dispensed the chemical
reaction taking place inside the battery heats up the chemicals and in
turn the casing. To give you an idea of the difference in a battery you
use to the type installed in a KERS system: A small AA battery has a
discharge rate of just less than 10,000 Joules or 1Kj, a KERS battery
can store 400KJ's so that's 400 times the storage capacity. Heatsoak
can be a massive factor in the performance of both the batteries life
and performance. The more heat the battery is exposed to the faster the
cells degrade and the less effective the cells produce optimum power.
Energy
Harvesting is when the electrical motor connected to the crankshaft on
the front of the engine withdraws power under braking (engine braking)
which has an effect on the balance of the car. This is why you see
drivers adjusting their brake balance during the lap. The team that can best manage the transition between harvesting, energy storage, battery cooling and energy release will attain the best system. This I believe is why Red Bull now have Super Capacitors located at the rear of the floor. These Super Capacitors help to store and release energy more quickly than the larger batteries housed under the drivers seat. Cooling them will require a more intense level of airflow and that's why they have been situated near the starter hole as it almost sucks airflow into that region.

Mechanical & Aerodynamic Platform

If we take a look at the
RB8 and CT-01's main features it's clear to see the disparity in both mechanical &
aerodynamic performance between the two. This comes mainly from Red
Bull's desire to win and clear determination to provide an effective
aerodynamic platform.

Looking quickly at the 2
images above will leave you with very little to tell the differences
between the two packages. However on closer inspection there are
many details that differ here (Please bear in mind that the photo has
been taken at different zoom levels and at different angles and so
the 2 photos aren't a true 100% representation of the same thing. We
also have to remember that we don't know what fuel loads are onboard
either car which could also affect the way in which the cars
look/operate):

Mechanical

Firstly the ride height,
the Red Bull car is running closer to the tarmac as we can see by the
distance the front wing and skid block are from the tarmac. This not only has an effect on the suspension but the aerodynamic platform, you'll note that
all of the suspension elements are much more upright on the Caterham
this invariably leads to less motion available and in turn less
adjustability. The CT-01 would also seem more softly
sprung as you can see by the weight transference. The weight of the
car is leaning over on the right of the car as the weight shifts
under cornering load. Due to the softer suspension approach we can see the
additional angle of attack that the Caterham driver is having to take
in order to get around the same corner. Both the wheel angle and
drivers hand position show the Caterhams deficiency to the Red Bull.

In order to attain more grip we
can see that the CT-01 is also running with less air pressure in the
tyres. This is shown as the tyre bulges off the rim. Lower tyre
pressures help to squat the tyre on the rim giving a larger contact
patch which in turn gives up more grip. The problem with less tyre
pressure is it also dissolves some of the suspensions work. Due to
the tyre having less inflation the weight of the car acts on the
sidewalls creating squish. This squish acts as a form of suspension
and counteracts some of the suspensions actions. I'm not saying
running with massive tyre pressures is good either as that can create
deflection and have the opposite also non desirable effect on the
suspension. Finding a happy medium between the two will result in a
much more responsive suspension.

One of the larger problems with more
body roll is that you spend more time cornering than your opposition
and as such will also have to run compromised gear ratio's in order
to corner in the right rev range.

Aerodynamically

The front of the nose cone on the RB8
has a much more bulbous frontal area which is in stark contrast to
the CT-01's almost pointed nose. The RB8's nose
design is all about continued flow management in order to feed/push
the airflow into the path of the next component. The CT-01's nose is
a much more blunt design with perhaps the highest possible nose
configuration available. This is done to try and drive more air
under the car towards the floor and speed up the airflow to the
diffuser beyond.

The step nose that
features on most of the cars this season is a direct response to the
teams wanting to get as much air under the nose to the
floor as possible. When EBD (Exhaust Blow Diffusers) were in use this wasn't such a huge requirement as the exhausts fed the diffuser with more than enough airflow. This meant the air from the front of the car could be directed at both the underside and top side of the floor.

Red Bull's nose slot in the step area helps to
stop flow detachment that usually occurs when airflow meets with a
sheer surface. The step or ramp of the nose design although
minimally will create some drag. This disadvantage has been deemed
acceptable by the teams to gain the air underneath.

The Front wing planes used by
the two teams are very similar in design even with the top element
sporting similar pointed ends at the inner edge of the element. The
RB8's front wing however has additional pylons/vanes just infront of
this area that combine with the top element in order to generate flow
vortices. These vortices travel at a higher speed than a normal
laminar flow. In the case of the RB8 these vortices are then targeted
at the turning vanes behind (mounted below the nosecone) in order to
direct the flow further down the car. As Caterham don't have these
pylons/vanes the vortice(s) generated from the wing tip is much
smaller and so the turning vanes are also designed more neutrally.

The picture above is a very crude explanation (in 2D) to explain what I mean by a votice or vortex, the two wing tips create airflow that act on one another sending the airflow into a spin and create a higher speed airflow we call a vortice.

The frontal entry
point of the Sidepods of both cars are very similar dimensionally
however where the top of the Sidepod on the RB8 slopes inward toward
the cockpit the CT-01's lean away. The reason Red Bull follow that
ethos is this helps to funnel the airflow towards the rear of the car creating a downwash towards the rear of the floor. Caterham's version will allow the airflow to tumble off the
sides towards the floor and so less flow is contained and sent towards the rear floor. Although both cars run the same engine due
to mapping requirements their cooling methods may differ and so
radiator size and layout will differ between the two cars. This
leads to the difference in sidepod size and shape (packaging).

Due to the
requirement to vent the exhaust in a specified way this year design
and integration of the exhaust remains a key element of this years
car designs. The exhaust gases can be used to manipulate airflow and
generate additional downforce when used in the correct way. Red
Bulls approach to this is to create a ramp at the rear end of the
sidepod with a channel to direct the exhaust/exhaust plume.
Positioning/Angling the ramp and channel is vital in helping to draw
the airflow coming across the top of the sidepod and from around the
sidepod toward the exhaust plume which in turn directs the flow
toward the rear of the floor. Doing this helps to generate
downforce.

The CT-01's exhaust
solution is higher on the body and deals more directly with the
airflow from the top of the sidepod than the air travelling around
the side. The Shark Gills that cover the exhaust are there to try
and keep the airflow attached from the top and side of the sidepod
and also reduce the boudary layer speeding up the flow heading toward
the exhaust plume. (The Shark Gills are ejecting air that comes
through the sidepod entry) The exhaust plume at this higher point on
the car does not provide as much airflow toward the rear of the floor
as it's Red Bull counterpart and so generates downforce on other
area's including the beam wing.

The rear wing has
become an area in which much more performance can be extracted than
simply by adjusting the wings angle of attack. The beam or beam wing
as most call it creates a level of downforce aswell as providing the
wings attachment to the car. This area is now designed in order to
achieve additional downforce shaped like a wing plane. Some designs
are much more complex than others but it's design/usage is very much
determined by the airflow presented to it by the components in front
of it. Rear wing design has altered since the inception of DRS as
teams try to balance the effects of using or not using the DRS
system. Designing the heights of the two wing planes will effect not
only the angle of attack that can be implemented in the closed
position but also the effect of the effectiveness of DRS when active.
This is a tuning decision made based upon the circuits
characteristics.

The louvres that you
see at the front edge of the wing endplates are used to reduce drag
at the rear wing tips. Robbing airflow from one side of the endplate
and sending it to the other thus affecting the airflow and reducing
the drag.

To add additional
downforce the rules permit a Gurney Flap on the trailing edge of the
rear wing plane. If used it helps to stunt the flow and forces the
air backwards causing the air to spiral against itself creating more
downforce.

In the case of the
two rear wing designs from Red Bull and Caterham there is nothing
major in design philosophy between the two with very similar
endplates except at the rear where the RB8 has trailing strakes that
will manipulate the airflow and help guide any airflow exiting the
rear of the car.

The diffuser is
obviously a key area in extracting rear downforce from an F1 car.
Over the last few years the teams have exposed loopholes within the
regulations in order to better extract more downforce. Each year the
FIA has to re clarify areas within the technical regulations to try
and reduce the amount of downforce the teams can generate. The
latest of these has been the removal of EBD (Exhaust Blow Diffusers)
unlike the top exiting exhausts of this season the exhausts used
to channel their airflow in a cavity in the floor of the car in order
to speed up the diffuser process and seal the diffuser edges. (When
we talk about sealing the diffuser this is achieved by creating a
channel of airflow, the stronger & wider the airflow the better
the effect. The term sealing is like creating a wall of airflow to
which outside airflow doesn't affect the performance with the diffuser channel.) Without EBD
this has become a much more difficult task and means the teams had to
start with a much narrower sealed area. This is all intrinsically
linked to Rake as we discussed earlier and depends heavily on how
much air can be driven underneath and over the rear of the
floor/diffuser.

Unlike when EBD
blocked it's passage into the diffuser airflow, tyre squirt has become
a factor for the teams to manage this season. Tyre Squirt is the air
that is pushed laterally off the sides of the tyre as it rotates.
This air, if not managed will push latterally into the diffuser flow
and upset the balance of the car. We have to remember that although
most of us can only visualise airflow in a uniform way (front to back
over the car) as the car turns and travels on it's suspension the
airflow is also moving. This means that managing an element like
tyre squirt can greatly affect the level of downforce and in turn the
balance of the car.

Just like the gurney flap I mentioned in the Rear Wing section the diffuser is also allowed a gurney flap in order to generate downforce. As we can see from the pictures above both teams again have very different
Philosophies in this area to attain better performance. Red Bull's Gurney flap is slightly detached from the diffusers edge, this allows the flap to work as a wing in unison with the diffusers top edge. This bleeds airflow through the gap allowing an element of flex and allows more downforce to be applied to the gurney flap as the low pressure air goes beneath the flap. Meanwhile the Gurney flap on the Caterham is a much more blunt approach with a sheer 90 degree surface at the maximum 20mm permissible surface area.

In Season Updates

This is perhaps one of the more important aspects of racing within a series like F1, as the season progresses and the team are able to find additional performance gains they are bought to each circuit to be evaluated. Updates come in either Mechanical or Aerodynamic forms and sometimes utilise both in order to gain either additional balance for the driver and/or extra downforce. For example this season has shown the depths and pure rate of development that Red Bull can achieve having produced at least 4 major different exhaust configurations in quick succession. To say that the teams always get things right would be wrong though, Red Bull chased their Sidepod/Tunnel/Exhaust solution for a number of races only to abandon it in favour of a more neutral solution. Sometimes the over complexity of a design can lead it impacting how it feels for the driver. In terms of the Tunnel solution Caterham also briefly tested a version of the same type of idea at Mugello. This is something that I intend to write an article on in the future but will briefly touch on it now: Aero Convergence is when a seemingly leading team has a key area of aerodynamic gain, other teams see this a way of extracting more performance from their own package and so develop their own iteration. McLaren's exhaust system this season highlights this brilliantly, with the clear advantage at Melbourne the teams invested their development time chasing similar solutions to the McLaren style exhaust.

Red Bull's Exhaust / Sidepod / Tunnel solution featured a section that was missing from the bottom edge of the sidepod and in its first iteration exited at the rear of the sidepod. The idea was that the airflow from around the side of sidepod would go through the tunnel and help produce an extremity of airflow above the diffuser to help seal it. Seemingly this worked in both the Wind Tunnel and CFD but when placed on the car didn't have the desired effect. Red Bull latterly exited the airflow inside the engine cover and presumably but abandoned this method too. I'm still not sure this is the last we will see of this design as the team refine how the airflow pattern works.

Caterham CT-01 - Mugello: As we can see from this picture Caterham did test an alternative exhaust solution at Mugello. The design centres around the same ethos as the Red Bull Tunnel with the exhaust placed in the lower position in an attempt to draw airflow into the tunnel below. The Caterham version exited the airflow into the engine cover and presumably out of the starter hole at the rear.

In Summary

Red Bull are no stranger
to the world of FIA rule changes / clarifications as they push the
boundaries and interpret the rules in a different way. Having
perhaps without the DDD (Double Deck Diffuser) the best car of 09 and
then using their facilities to rapidly catch and overtake the
initially superior Brawn GP car of that year. This was a year I
believe Red Bull learnt many lessons both on and off track in terms
of strategy, car design and how to handle the FIA's ever changing
rule book. In 2010 & 2011 they produced cars that leant on the
side of illegality and prospered using 09 as a yard stick for future
processes. More recently they have fell to the wroth of the FIA's ever
changing rule book and have had both their Floor and Front Brake
housings banned under rule clarifications. This won't stop the teams pushing ever closer to their interpretations of what is legal and illegal.

As we can see from
the disparity between these two teams, having the same/similar
engine/gearbox and ancillaries is not the only thing required to
produce a winning car. It's a multi faceted design process that
requires decisions on everything from engine mapping, exhaust tuning,
gear ratio selection, suspension geometry, tyre pressures,
aerodynamics to name a few. These processes are also reviewed and
changed based on the particular circuit F1 are visiting at the time.

In terms of running
an F1 team the costs are large, having invested a large sum of money
in their team Red Bull have reaped the rewards with the constructor
wins in 2010 & 2011 giving them a return on their investment
through the prize money received at the end of the season. In stark
contrast Caterham having been placed 10th
since its inception will receive a much smaller prize fund. As the
Caterham team continues to expand I expect their expectations will be
met with much better race placings giving them the opportunity to
shadow Red Bull Racing's success.

3 comments:

I barely have time to read what fellow bloggers are doiing, but this one is lovely detailed article, Matt, congratulations for that excellent writing.

MY humble contribution to the Red Bull arsenal would be their partnership with Leica and in particular the laser system that is supposed to check the materials and parts for defects. That way, RB7 became the most reliable car in 2011 after the bad 2010 season, where reliability have stolen lots of points.

Thanks for your positive comments, yes you are quite right about their Leica partnership being crucial in RBR's development. Trouble is how far you go with these blog posts as you can see this is a rather large one.

I now see why you did not want to rush this one. It has filled some gaps for me, it's a gem Matt. Will read it a few more times and try to glean more. My hopes of getting you on the big screen were scuppered by the WI they booked the room in the RB Legion. More interested in knitting..........I'll try again!

Whilst I'm trying to keep atop of the blog you may have noticed of late that there is less content appearing. For those of you that haven't realised, most of my work has now been moved over to Motorsport.com where I'm working with Giorgio Piola.

I'm still doing the technical image gallery for each GP with the continued support of friend of the site Sutton Images. However, as always my time is limited and so this might not be updated as quickly as it once was, so keep checking back.

As some of you may have found out already I'm also working with the Missed Apex crew on their podcast from time-to-time, either doing race reviews or dedicated 'Tech Time' shows.

I've embedded the latest version of the podcast below and will update this a frequently as I appear. However, please head over to Itunes if you want it to appear in your player when episodes are available. The show is great to work on and has a great lineup of 'regulars' but has also enticed some bigger names recently too, with Will Buxton and Bradley Philpot on shows during the summer break.

Total Pageviews

Social Media

Translate

Sutton Images

Sutton Images provide the best images direct from the action every GP weekend allowing me to show you just where and what the teams are improving.